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v5.4
  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 *  linux/arch/arm/mm/cache-v6.S
  4 *
  5 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
  6 *
  7 *  This is the "shell" of the ARMv6 processor support.
  8 */
  9#include <linux/linkage.h>
 10#include <linux/init.h>
 11#include <asm/assembler.h>
 12#include <asm/errno.h>
 13#include <asm/unwind.h>
 14
 15#include "proc-macros.S"
 16
 17#define HARVARD_CACHE
 18#define CACHE_LINE_SIZE		32
 19#define D_CACHE_LINE_SIZE	32
 20#define BTB_FLUSH_SIZE		8
 21
 
 
 22/*
 23 *	v6_flush_icache_all()
 24 *
 25 *	Flush the whole I-cache.
 26 *
 27 *	ARM1136 erratum 411920 - Invalidate Instruction Cache operation can fail.
 28 *	This erratum is present in 1136, 1156 and 1176. It does not affect the
 29 *	MPCore.
 30 *
 31 *	Registers:
 32 *	r0 - set to 0
 33 *	r1 - corrupted
 34 */
 35ENTRY(v6_flush_icache_all)
 36	mov	r0, #0
 37#ifdef CONFIG_ARM_ERRATA_411920
 38	mrs	r1, cpsr
 39	cpsid	ifa				@ disable interrupts
 40	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 41	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 42	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 43	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 44	msr	cpsr_cx, r1			@ restore interrupts
 45	.rept	11				@ ARM Ltd recommends at least
 46	nop					@ 11 NOPs
 47	.endr
 48#else
 49	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I-cache
 50#endif
 51	ret	lr
 52ENDPROC(v6_flush_icache_all)
 53
 54/*
 55 *	v6_flush_cache_all()
 56 *
 57 *	Flush the entire cache.
 58 *
 59 *	It is assumed that:
 60 */
 61ENTRY(v6_flush_kern_cache_all)
 62	mov	r0, #0
 63#ifdef HARVARD_CACHE
 64	mcr	p15, 0, r0, c7, c14, 0		@ D cache clean+invalidate
 65#ifndef CONFIG_ARM_ERRATA_411920
 66	mcr	p15, 0, r0, c7, c5, 0		@ I+BTB cache invalidate
 67#else
 68	b	v6_flush_icache_all
 69#endif
 70#else
 71	mcr	p15, 0, r0, c7, c15, 0		@ Cache clean+invalidate
 72#endif
 73	ret	lr
 74
 75/*
 76 *	v6_flush_cache_all()
 77 *
 78 *	Flush all TLB entries in a particular address space
 79 *
 80 *	- mm    - mm_struct describing address space
 81 */
 82ENTRY(v6_flush_user_cache_all)
 83	/*FALLTHROUGH*/
 84
 85/*
 86 *	v6_flush_cache_range(start, end, flags)
 87 *
 88 *	Flush a range of TLB entries in the specified address space.
 89 *
 90 *	- start - start address (may not be aligned)
 91 *	- end   - end address (exclusive, may not be aligned)
 92 *	- flags	- vm_area_struct flags describing address space
 93 *
 94 *	It is assumed that:
 95 *	- we have a VIPT cache.
 96 */
 97ENTRY(v6_flush_user_cache_range)
 98	ret	lr
 99
100/*
101 *	v6_coherent_kern_range(start,end)
102 *
103 *	Ensure that the I and D caches are coherent within specified
104 *	region.  This is typically used when code has been written to
105 *	a memory region, and will be executed.
106 *
107 *	- start   - virtual start address of region
108 *	- end     - virtual end address of region
109 *
110 *	It is assumed that:
111 *	- the Icache does not read data from the write buffer
112 */
113ENTRY(v6_coherent_kern_range)
114	/* FALLTHROUGH */
115
116/*
117 *	v6_coherent_user_range(start,end)
118 *
119 *	Ensure that the I and D caches are coherent within specified
120 *	region.  This is typically used when code has been written to
121 *	a memory region, and will be executed.
122 *
123 *	- start   - virtual start address of region
124 *	- end     - virtual end address of region
125 *
126 *	It is assumed that:
127 *	- the Icache does not read data from the write buffer
128 */
129ENTRY(v6_coherent_user_range)
130 UNWIND(.fnstart		)
131#ifdef HARVARD_CACHE
132	bic	r0, r0, #CACHE_LINE_SIZE - 1
1331:
134 USER(	mcr	p15, 0, r0, c7, c10, 1	)	@ clean D line
135	add	r0, r0, #CACHE_LINE_SIZE
136	cmp	r0, r1
137	blo	1b
138#endif
139	mov	r0, #0
140#ifdef HARVARD_CACHE
141	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
142#ifndef CONFIG_ARM_ERRATA_411920
143	mcr	p15, 0, r0, c7, c5, 0		@ I+BTB cache invalidate
144#else
145	b	v6_flush_icache_all
146#endif
147#else
148	mcr	p15, 0, r0, c7, c5, 6		@ invalidate BTB
149#endif
150	ret	lr
151
152/*
153 * Fault handling for the cache operation above. If the virtual address in r0
154 * isn't mapped, fail with -EFAULT.
155 */
1569001:
157	mov	r0, #-EFAULT
158	ret	lr
159 UNWIND(.fnend		)
160ENDPROC(v6_coherent_user_range)
161ENDPROC(v6_coherent_kern_range)
162
163/*
164 *	v6_flush_kern_dcache_area(void *addr, size_t size)
165 *
166 *	Ensure that the data held in the page kaddr is written back
167 *	to the page in question.
168 *
169 *	- addr	- kernel address
170 *	- size	- region size
171 */
172ENTRY(v6_flush_kern_dcache_area)
173	add	r1, r0, r1
174	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
1751:
176#ifdef HARVARD_CACHE
177	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
178#else
179	mcr	p15, 0, r0, c7, c15, 1		@ clean & invalidate unified line
180#endif	
181	add	r0, r0, #D_CACHE_LINE_SIZE
182	cmp	r0, r1
183	blo	1b
184#ifdef HARVARD_CACHE
185	mov	r0, #0
186	mcr	p15, 0, r0, c7, c10, 4
187#endif
188	ret	lr
189
190
191/*
192 *	v6_dma_inv_range(start,end)
193 *
194 *	Invalidate the data cache within the specified region; we will
195 *	be performing a DMA operation in this region and we want to
196 *	purge old data in the cache.
197 *
198 *	- start   - virtual start address of region
199 *	- end     - virtual end address of region
200 */
201v6_dma_inv_range:
202#ifdef CONFIG_DMA_CACHE_RWFO
203	ldrb	r2, [r0]			@ read for ownership
204	strb	r2, [r0]			@ write for ownership
205#endif
206	tst	r0, #D_CACHE_LINE_SIZE - 1
207	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
208#ifdef HARVARD_CACHE
209	mcrne	p15, 0, r0, c7, c10, 1		@ clean D line
210#else
211	mcrne	p15, 0, r0, c7, c11, 1		@ clean unified line
212#endif
213	tst	r1, #D_CACHE_LINE_SIZE - 1
214#ifdef CONFIG_DMA_CACHE_RWFO
215	ldrbne	r2, [r1, #-1]			@ read for ownership
216	strbne	r2, [r1, #-1]			@ write for ownership
217#endif
218	bic	r1, r1, #D_CACHE_LINE_SIZE - 1
219#ifdef HARVARD_CACHE
220	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D line
221#else
222	mcrne	p15, 0, r1, c7, c15, 1		@ clean & invalidate unified line
223#endif
2241:
225#ifdef HARVARD_CACHE
226	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D line
227#else
228	mcr	p15, 0, r0, c7, c7, 1		@ invalidate unified line
229#endif
230	add	r0, r0, #D_CACHE_LINE_SIZE
231	cmp	r0, r1
232#ifdef CONFIG_DMA_CACHE_RWFO
233	ldrlo	r2, [r0]			@ read for ownership
234	strlo	r2, [r0]			@ write for ownership
235#endif
236	blo	1b
237	mov	r0, #0
238	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
239	ret	lr
240
241/*
242 *	v6_dma_clean_range(start,end)
243 *	- start   - virtual start address of region
244 *	- end     - virtual end address of region
245 */
246v6_dma_clean_range:
247	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
2481:
249#ifdef CONFIG_DMA_CACHE_RWFO
250	ldr	r2, [r0]			@ read for ownership
251#endif
252#ifdef HARVARD_CACHE
253	mcr	p15, 0, r0, c7, c10, 1		@ clean D line
254#else
255	mcr	p15, 0, r0, c7, c11, 1		@ clean unified line
256#endif
257	add	r0, r0, #D_CACHE_LINE_SIZE
258	cmp	r0, r1
259	blo	1b
260	mov	r0, #0
261	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
262	ret	lr
263
264/*
265 *	v6_dma_flush_range(start,end)
266 *	- start   - virtual start address of region
267 *	- end     - virtual end address of region
268 */
269ENTRY(v6_dma_flush_range)
270#ifdef CONFIG_DMA_CACHE_RWFO
271	ldrb	r2, [r0]		@ read for ownership
272	strb	r2, [r0]		@ write for ownership
273#endif
274	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
2751:
276#ifdef HARVARD_CACHE
277	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
278#else
279	mcr	p15, 0, r0, c7, c15, 1		@ clean & invalidate line
280#endif
281	add	r0, r0, #D_CACHE_LINE_SIZE
282	cmp	r0, r1
283#ifdef CONFIG_DMA_CACHE_RWFO
284	ldrblo	r2, [r0]			@ read for ownership
285	strblo	r2, [r0]			@ write for ownership
286#endif
287	blo	1b
288	mov	r0, #0
289	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
290	ret	lr
291
292/*
293 *	dma_map_area(start, size, dir)
294 *	- start	- kernel virtual start address
295 *	- size	- size of region
296 *	- dir	- DMA direction
297 */
298ENTRY(v6_dma_map_area)
299	add	r1, r1, r0
300	teq	r2, #DMA_FROM_DEVICE
301	beq	v6_dma_inv_range
302#ifndef CONFIG_DMA_CACHE_RWFO
303	b	v6_dma_clean_range
304#else
305	teq	r2, #DMA_TO_DEVICE
306	beq	v6_dma_clean_range
307	b	v6_dma_flush_range
308#endif
309ENDPROC(v6_dma_map_area)
310
311/*
312 *	dma_unmap_area(start, size, dir)
313 *	- start	- kernel virtual start address
314 *	- size	- size of region
315 *	- dir	- DMA direction
316 */
317ENTRY(v6_dma_unmap_area)
318#ifndef CONFIG_DMA_CACHE_RWFO
319	add	r1, r1, r0
320	teq	r2, #DMA_TO_DEVICE
321	bne	v6_dma_inv_range
322#endif
323	ret	lr
324ENDPROC(v6_dma_unmap_area)
325
326	.globl	v6_flush_kern_cache_louis
327	.equ	v6_flush_kern_cache_louis, v6_flush_kern_cache_all
328
329	__INITDATA
330
331	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
332	define_cache_functions v6
v6.2
  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 *  linux/arch/arm/mm/cache-v6.S
  4 *
  5 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
  6 *
  7 *  This is the "shell" of the ARMv6 processor support.
  8 */
  9#include <linux/linkage.h>
 10#include <linux/init.h>
 11#include <asm/assembler.h>
 12#include <asm/errno.h>
 13#include <asm/unwind.h>
 14
 15#include "proc-macros.S"
 16
 17#define HARVARD_CACHE
 18#define CACHE_LINE_SIZE		32
 19#define D_CACHE_LINE_SIZE	32
 20#define BTB_FLUSH_SIZE		8
 21
 22.arch armv6
 23
 24/*
 25 *	v6_flush_icache_all()
 26 *
 27 *	Flush the whole I-cache.
 28 *
 29 *	ARM1136 erratum 411920 - Invalidate Instruction Cache operation can fail.
 30 *	This erratum is present in 1136, 1156 and 1176. It does not affect the
 31 *	MPCore.
 32 *
 33 *	Registers:
 34 *	r0 - set to 0
 35 *	r1 - corrupted
 36 */
 37ENTRY(v6_flush_icache_all)
 38	mov	r0, #0
 39#ifdef CONFIG_ARM_ERRATA_411920
 40	mrs	r1, cpsr
 41	cpsid	ifa				@ disable interrupts
 42	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 43	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 44	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 45	mcr	p15, 0, r0, c7, c5, 0		@ invalidate entire I-cache
 46	msr	cpsr_cx, r1			@ restore interrupts
 47	.rept	11				@ ARM Ltd recommends at least
 48	nop					@ 11 NOPs
 49	.endr
 50#else
 51	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I-cache
 52#endif
 53	ret	lr
 54ENDPROC(v6_flush_icache_all)
 55
 56/*
 57 *	v6_flush_cache_all()
 58 *
 59 *	Flush the entire cache.
 60 *
 61 *	It is assumed that:
 62 */
 63ENTRY(v6_flush_kern_cache_all)
 64	mov	r0, #0
 65#ifdef HARVARD_CACHE
 66	mcr	p15, 0, r0, c7, c14, 0		@ D cache clean+invalidate
 67#ifndef CONFIG_ARM_ERRATA_411920
 68	mcr	p15, 0, r0, c7, c5, 0		@ I+BTB cache invalidate
 69#else
 70	b	v6_flush_icache_all
 71#endif
 72#else
 73	mcr	p15, 0, r0, c7, c15, 0		@ Cache clean+invalidate
 74#endif
 75	ret	lr
 76
 77/*
 78 *	v6_flush_cache_all()
 79 *
 80 *	Flush all TLB entries in a particular address space
 81 *
 82 *	- mm    - mm_struct describing address space
 83 */
 84ENTRY(v6_flush_user_cache_all)
 85	/*FALLTHROUGH*/
 86
 87/*
 88 *	v6_flush_cache_range(start, end, flags)
 89 *
 90 *	Flush a range of TLB entries in the specified address space.
 91 *
 92 *	- start - start address (may not be aligned)
 93 *	- end   - end address (exclusive, may not be aligned)
 94 *	- flags	- vm_area_struct flags describing address space
 95 *
 96 *	It is assumed that:
 97 *	- we have a VIPT cache.
 98 */
 99ENTRY(v6_flush_user_cache_range)
100	ret	lr
101
102/*
103 *	v6_coherent_kern_range(start,end)
104 *
105 *	Ensure that the I and D caches are coherent within specified
106 *	region.  This is typically used when code has been written to
107 *	a memory region, and will be executed.
108 *
109 *	- start   - virtual start address of region
110 *	- end     - virtual end address of region
111 *
112 *	It is assumed that:
113 *	- the Icache does not read data from the write buffer
114 */
115ENTRY(v6_coherent_kern_range)
116	/* FALLTHROUGH */
117
118/*
119 *	v6_coherent_user_range(start,end)
120 *
121 *	Ensure that the I and D caches are coherent within specified
122 *	region.  This is typically used when code has been written to
123 *	a memory region, and will be executed.
124 *
125 *	- start   - virtual start address of region
126 *	- end     - virtual end address of region
127 *
128 *	It is assumed that:
129 *	- the Icache does not read data from the write buffer
130 */
131ENTRY(v6_coherent_user_range)
132 UNWIND(.fnstart		)
133#ifdef HARVARD_CACHE
134	bic	r0, r0, #CACHE_LINE_SIZE - 1
1351:
136 USER(	mcr	p15, 0, r0, c7, c10, 1	)	@ clean D line
137	add	r0, r0, #CACHE_LINE_SIZE
138	cmp	r0, r1
139	blo	1b
140#endif
141	mov	r0, #0
142#ifdef HARVARD_CACHE
143	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
144#ifndef CONFIG_ARM_ERRATA_411920
145	mcr	p15, 0, r0, c7, c5, 0		@ I+BTB cache invalidate
146#else
147	b	v6_flush_icache_all
148#endif
149#else
150	mcr	p15, 0, r0, c7, c5, 6		@ invalidate BTB
151#endif
152	ret	lr
153
154/*
155 * Fault handling for the cache operation above. If the virtual address in r0
156 * isn't mapped, fail with -EFAULT.
157 */
1589001:
159	mov	r0, #-EFAULT
160	ret	lr
161 UNWIND(.fnend		)
162ENDPROC(v6_coherent_user_range)
163ENDPROC(v6_coherent_kern_range)
164
165/*
166 *	v6_flush_kern_dcache_area(void *addr, size_t size)
167 *
168 *	Ensure that the data held in the page kaddr is written back
169 *	to the page in question.
170 *
171 *	- addr	- kernel address
172 *	- size	- region size
173 */
174ENTRY(v6_flush_kern_dcache_area)
175	add	r1, r0, r1
176	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
1771:
178#ifdef HARVARD_CACHE
179	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
180#else
181	mcr	p15, 0, r0, c7, c15, 1		@ clean & invalidate unified line
182#endif	
183	add	r0, r0, #D_CACHE_LINE_SIZE
184	cmp	r0, r1
185	blo	1b
186#ifdef HARVARD_CACHE
187	mov	r0, #0
188	mcr	p15, 0, r0, c7, c10, 4
189#endif
190	ret	lr
191
192
193/*
194 *	v6_dma_inv_range(start,end)
195 *
196 *	Invalidate the data cache within the specified region; we will
197 *	be performing a DMA operation in this region and we want to
198 *	purge old data in the cache.
199 *
200 *	- start   - virtual start address of region
201 *	- end     - virtual end address of region
202 */
203v6_dma_inv_range:
204#ifdef CONFIG_DMA_CACHE_RWFO
205	ldrb	r2, [r0]			@ read for ownership
206	strb	r2, [r0]			@ write for ownership
207#endif
208	tst	r0, #D_CACHE_LINE_SIZE - 1
209	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
210#ifdef HARVARD_CACHE
211	mcrne	p15, 0, r0, c7, c10, 1		@ clean D line
212#else
213	mcrne	p15, 0, r0, c7, c11, 1		@ clean unified line
214#endif
215	tst	r1, #D_CACHE_LINE_SIZE - 1
216#ifdef CONFIG_DMA_CACHE_RWFO
217	ldrbne	r2, [r1, #-1]			@ read for ownership
218	strbne	r2, [r1, #-1]			@ write for ownership
219#endif
220	bic	r1, r1, #D_CACHE_LINE_SIZE - 1
221#ifdef HARVARD_CACHE
222	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D line
223#else
224	mcrne	p15, 0, r1, c7, c15, 1		@ clean & invalidate unified line
225#endif
2261:
227#ifdef HARVARD_CACHE
228	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D line
229#else
230	mcr	p15, 0, r0, c7, c7, 1		@ invalidate unified line
231#endif
232	add	r0, r0, #D_CACHE_LINE_SIZE
233	cmp	r0, r1
234#ifdef CONFIG_DMA_CACHE_RWFO
235	ldrlo	r2, [r0]			@ read for ownership
236	strlo	r2, [r0]			@ write for ownership
237#endif
238	blo	1b
239	mov	r0, #0
240	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
241	ret	lr
242
243/*
244 *	v6_dma_clean_range(start,end)
245 *	- start   - virtual start address of region
246 *	- end     - virtual end address of region
247 */
248v6_dma_clean_range:
249	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
2501:
251#ifdef CONFIG_DMA_CACHE_RWFO
252	ldr	r2, [r0]			@ read for ownership
253#endif
254#ifdef HARVARD_CACHE
255	mcr	p15, 0, r0, c7, c10, 1		@ clean D line
256#else
257	mcr	p15, 0, r0, c7, c11, 1		@ clean unified line
258#endif
259	add	r0, r0, #D_CACHE_LINE_SIZE
260	cmp	r0, r1
261	blo	1b
262	mov	r0, #0
263	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
264	ret	lr
265
266/*
267 *	v6_dma_flush_range(start,end)
268 *	- start   - virtual start address of region
269 *	- end     - virtual end address of region
270 */
271ENTRY(v6_dma_flush_range)
272#ifdef CONFIG_DMA_CACHE_RWFO
273	ldrb	r2, [r0]		@ read for ownership
274	strb	r2, [r0]		@ write for ownership
275#endif
276	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
2771:
278#ifdef HARVARD_CACHE
279	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
280#else
281	mcr	p15, 0, r0, c7, c15, 1		@ clean & invalidate line
282#endif
283	add	r0, r0, #D_CACHE_LINE_SIZE
284	cmp	r0, r1
285#ifdef CONFIG_DMA_CACHE_RWFO
286	ldrblo	r2, [r0]			@ read for ownership
287	strblo	r2, [r0]			@ write for ownership
288#endif
289	blo	1b
290	mov	r0, #0
291	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
292	ret	lr
293
294/*
295 *	dma_map_area(start, size, dir)
296 *	- start	- kernel virtual start address
297 *	- size	- size of region
298 *	- dir	- DMA direction
299 */
300ENTRY(v6_dma_map_area)
301	add	r1, r1, r0
302	teq	r2, #DMA_FROM_DEVICE
303	beq	v6_dma_inv_range
304#ifndef CONFIG_DMA_CACHE_RWFO
305	b	v6_dma_clean_range
306#else
307	teq	r2, #DMA_TO_DEVICE
308	beq	v6_dma_clean_range
309	b	v6_dma_flush_range
310#endif
311ENDPROC(v6_dma_map_area)
312
313/*
314 *	dma_unmap_area(start, size, dir)
315 *	- start	- kernel virtual start address
316 *	- size	- size of region
317 *	- dir	- DMA direction
318 */
319ENTRY(v6_dma_unmap_area)
320#ifndef CONFIG_DMA_CACHE_RWFO
321	add	r1, r1, r0
322	teq	r2, #DMA_TO_DEVICE
323	bne	v6_dma_inv_range
324#endif
325	ret	lr
326ENDPROC(v6_dma_unmap_area)
327
328	.globl	v6_flush_kern_cache_louis
329	.equ	v6_flush_kern_cache_louis, v6_flush_kern_cache_all
330
331	__INITDATA
332
333	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
334	define_cache_functions v6